Dawn of War: Sync Kills

From RelicWiki

Sync Kills

When two units are fighting in close combat with each other, if one lands the kill blow on the other and the defeated unit is an infantry unit, a special animation takes place called a sync kill. Which animation takes place is highly dependent on what two units are fighting, and can range from the mundane point blank firing of one infantry unit at another to unique sync kills such as the ever impressive Force Commander eliminating the Bloodthirster. When entering a sync kill, the victor gains invulnerability to physical damage until the animation has completed but loses its melee cover bonuses if it had them. A unit can still break morale during a sync kill.

Most infantry and melee-capable vehicles are guaranteed to perform a sync kill when they defeat an enemy infantry unit, but certain units have a reduced chance to perform a sync kill. Some units also have a limited set of possible sync kills they can perform and other units have a limited set of sync kills they can receive, so even if a unit is guaranteed to perform sync kills it may not do so against certain units. Because sync kills can allow overwhelmed melee units to last much longer than usual, the reduced sync kill rate prevents them from becoming too powerful against ranged armies. Some units also lack sync kill animations entirely and so cannot perform sync kills at all, although they can still be the victims of them.

Finally, certain units have special sync kills that they will only use against one other enemy, such as the aforementioned Force Commander defeating a Bloodthirster. These special sync kills are even more spectacular than the regular variety and are always worth watching. Special sync kills can be for vehicle vs vehicle combat, something that regular sync kills cannot do. Special sync kills are guaranteed to fire for that matchup when a sync kill is performed (although remember that Grey Knights only have a 50% chance to perform a sync kill at all).

Tactics

Sync kills have significant tactical importance, due to the invulnerability granted while active. Units who have many sync kills can wade into close combat with infantry and emerge nearly unscathed, even when fire is focused on the sync killing unit. For instance, if a Necron Wraith attacks a full squad of Ork Slugga Boyz, the Wraith will enter sync kills often enough that most of the Slugga Boyz will be unable to damage it. If your units are the victim of a sync kill from a particularly dangerous unit, such as a commander or melee uber unit, use the short moment of freedom to disengage from melee and gain some distance from the unit, leaving it completely exposed once the sync kill is complete.